<form class="form-signin" ng-submit="login()" novalidate>
    <h2 class="form-signin-heading">Please sign in</h2>
    <label for="inputUserName" class="sr-only">用户名</label>
    <input type="text" id="inputUserName" class="form-control" placeholder="请输入用户名" required ng-model="user.username">
    <label for="inputPassword" class="sr-only">密&emsp;码</label>
    <input type="password" id="inputPassword" class="form-control" placeholder="请输入密码" required  ng-model="user.password">
    <div class="checkbox">
        <label>
            <input type="checkbox" value="remember-me"> 记住用户名
        </label>
    </div>
    <button class="btn btn-lg btn-primary btn-block" type="submit">Sign in</button>
</form>